There is a need for a method and system capable of efficiently and effectively filtering pollutants from exhaust gases. Although there are a number of devices available which are useful for filtering and catalyzing combustion gases or chemical reactions, each of these devices is incapable of providing an effective method for reducing pollutants cost effectively for the reasons described herein. It is generally acknowledged that the functional efficiency of combustion engines is directly related to the engine's ability to discharge gas created during the combustion process. One key element of the efficient discharge of gas is the existence of an adequate amount of counter-pressure at the precise time during the combustion process. This is an issue that has largely been ignored in creating these devices.
In general, an internal engine of combustion operates from the explosion of an air/fuel mixture that causes the expansion of the gases that move the piston of a cylinder. At the end of this cycle, an escape valve opens and the burnt gases are expelled at an extraordinary speed and sound. The performance of a combustion engine is affected by a variety of factors, including the quality of the fuel, pressure under which the fuel ignites, etc.
Because of the importance of relationship between fuel and air in the combustion mixture, the engines in most vehicles or devices are controlled by an electronic injection system. When fuel and air are mixed, the spark plug ignites and causes the explosion that puts into motion some parts of the engine, thus enabling the vehicle or device to move. The result of this “explosion” inside the engine also produces a variety of pollutant gases which are eliminated through the exhaust system. Some of these gases are: water vapor (H2O); carbon dioxide (CO2); nitrogen (N2); carbon monoxide (CO); hydrocarbons (HxCy); nitrogen oxide (N2O); hydrogen (H); methane (CH4); and oxygen (O2). The most toxic gases to human beings are: carbon monoxide (CO) which reduces the oxygenation of the blood, affects the nervous system, worsens cardiac and respiratory illnesses, and can cause fatigue and migraine in low concentrations and death in high concentrations; hydrocarbon (HxCy); and nitrogen oxide (N2O) which affects the lungs and heart, can cause bronchitis, acid deposition and diminishes the atmospheric visibility.
Once a optimal performance of a combustion engine is achieved, the system metrics of the optimal system can be used as a reference against which to measure the effect of various changes to the exhaust system, such as the collector, the catalytic converter, the diameters of the pipe, and the systems for the elimination of noise. By altering characteristics of the system, it is possible to minimize the emission of harmful gases generated during combustion by increasing the periods of low pressure between gas emissions from the explosions.
Besides the production of gases, burning fuel produces material particles (MP) that vary in composition in relation to, among other things, the type of fuel, the quality of the engine maintenance and also in relation to the working temperature of the engine. The material particles are formed from the agglomeration of hydrocarbons that are not combusted and water and impurities of the fuel to the nuclei of chemical carbon element. Material particulates can be inhaled and lodged in deep areas of the human lung, for example, and are widely considered to be an irritating agent for respiratory airways. These particles cause pulmonary illnesses that afflict the elderly and children mainly and in particular during the colder months of the year, when the temperatures are extremely low, a fact that increases the concentration of material particles. This process of contamination increases the cancerous elements that might possibly exist in material particles. It is also important to consider the other undesirable effects in the atmosphere, such as the reduction of visibility and the worsening of the “greenhouse effect”.
The material particles generally show a great dimensional variation. This variation causes any type of porous filter to a precocious saturation that, in turn, provokes functional overload to the components of the engine, resulting in an increase of fuel consumption, diminished power of the engine, increase of the volume of gases emitted during the combustion process, increase of temperature, and possible destruction of the engine.
With the knowledge about problems caused by these gases, several components designed to assist in the emission control have been developed. Amongst the most important are electronic control unit (“E.C.U.”), the lambda sensor, the EGR valve and the catalytic converter. The control of the air/fuel admission made by the E.C.U. is simply a microcontroller (microprocessor with embedded RAM and ROM memories, wherein the ROM already comes from the factory with specific program recorded on to it) making use of entrances of analog and digital exits, gathering the signals such as temperature and speed obtained from sensors. The E.C.U. searches in its entries for the sensors conditions. The software program recorded in its ROM analyses this data and, according to the programmed information, considers power, economy, and pollution factors to determine and implement the point of work of the valve of shock and the actuator of the impeller.
The lambda sensor is typically located in the exhaust system. It measures the amount of oxygen molecules that have not been consumed in the combustion process and which are therefore expelled together with the combusted gases through the exhaust pipe. This way, the computer will command the injection of more fuel in case there are excess oxygen molecules or, alternatively, to inject less fuel in cases where there are fewer oxygen molecules. By enriching or impoverishing the air/fuel mixture, the engine will work more efficiently, polluting much less, wasting less fuel and with less maintenance. Lambda is the ratio of amount of air available for combustion to the amount of air required for combustion to be stoichiometric. The desired value of lambda is one (1) which indicates that the combustion is perfect.
At the exit of the sensor is an electric signal of a voltage that is proportional to the amount of oxygen in the combusted gases and this voltage, in turn, is proportional to the air/fuel ratio. The ECU controls adjustments in the position in the actuator of the impeller and in the position of the shock valve, resulting in a richer air/fuel mixture (more combustible) or a leaner air/fuel mixture (less combustible). While the engine is warming up, the shock valve is kept partially closed, thereby allowing a richer air/fuel mixture (i.e. more fuel). In the neutral gear, the shock valve is adjusted to a lambda value of 1, while during low speed the impeller is kept partially closed, thus saving in fuel. In the other gears, the ECU shock valve is adjusted according to settings which are adopted to optimize power and economy and minimize pollution. In electronic management, this valve is controlled by the Electronic Control Module which uses actuators to determine the moment and the time where it must operate and its real performance monitored for a present potentiometer in the proper valve. This, in effect, will be part of the subject matter described herein.
The EGR valve controls the flux and the moment where these gases must be absorbed in the combustion chamber. The valve must be open under each of the following conditions: warm engine; rotation of the superior engine to the one of the idling; diverse conditions of acceleration and deceleration of the engine. The amount of the exhaust gases existing in the chamber, and the time that the valve remains open, will depend on the changes in the vacuum and the pressure of the exhaust pipe gases, in accordance with the pattern of the work of the engine. The exhaust gases are a mixture of combusted fuels and, as a result, they are no longer combustible. Moreover, if they occupy too much space in the chamber, they will limit the combustion of the air/fuel mixture, consequently diminishing its temperature. By reducing the temperature, the level of formation of nitrogen oxides produced by the engine is also reduced.
The catalytic converter, located in the exhaust system behind the lambda sensor, functions as a filter that reacts chemically, transforming the harmful gases that still remain in the exhaust stream. Behind the catalytic converter, is the muffler or silencer which must attenuate the sound and dampen the vibrations from the beat of the chain of gases (through bulkheads and with the flux passing through a series of punched pipes and chambers,) absorb the sound waves and control the counter-pressure.
Both the catalytic converter and the muffler are designed to cause a certain counter-pressure in the exhaust system. Without the correct control of the counter-pressure, the exhaust system becomes extremely damaging to the performance of the engine. It will be apparent to those skilled in the art that an engine at optimal performance gets the maximum power from a displacement of the piston, and proper discharge of the exit gases serves to generate maximum power and, therefore, the best performance. A double valve/escape system offers restrictive conditions, creating the counter-pressure.
Even the fuel engine, with the current technology, presents an excess of emissions of gases and material particles in the atmosphere. The ability to get the maximum power and performance is directly linked to the exhaust of the gases from the exhaust pipe. The exhaust process must account for the emission of gases when the engine is running at maximum power. When the engine operates outside of this parameter, resulting in a super dimensioned exhaustion, it will not have the proper restriction of the gases to get the best power and performance from the engine. This causes areas of low pressure resulting in waves of explosion of the gases in the engine causing an unnecessary increase of the emissions of gases and the increase of fuel consumption.
Mercedes-Benz of Brazil has published a report on the development and manufacturing of devices such as filter for material particles entitled “The Commercial Vehicles and the Environment” which verifies much of the foregoing information. Besides this report, it is generally known that a test using a filter of material particles in a fleet of vehicles that circulates in the urban environment was conducted by Mercedes-Benz GAC.—Germany. The filter in this study was made by means of a rolled ceramic wire net in a pipe that, in turn, was installed in the interior of a carcass, which replaces the muffler installed in the exhaust pipe of the automobile. In this configuration, a system of catalytic regeneration is used in the burning of the material particles that are deposited in the filter, keeping the restriction of the gases to the acceptable levels for the current environmental legislation once the device is automatically set in motion during the operation of the automobile.
One device for reducing emissions is described in U.S. patent application Ser. No. 11/204,324 filed Nov. 2, 2005 comprises a metallic cylindrical carcass with bevelled opening in a diagonal line in its posterior part where it is affixed by a clamp to an exhaust system or escape and its anterior part is adapted affix to a metallic capsule. However, this device does not include a fibrous blanket and the corresponding benefits associated therewith.
Despite the promoted efficiency of the methods and systems of the prior art, many are encumbered by high costs of manufacturing and therefore are impracticable from the commercial point of view, particularly for use with existing automobiles.